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Communications in Theoretical Physics 2009年第7期52卷 7-11页

作者： cui jin-chao JIA Li-Qun ZHANG Yao-Yu School of Science Jiangnan University Wuxi 214122 China Electric and Information Engineering College Pingdingshall University Pingdingshan 467002 China

Mei symmetry and Mei conserved quantity for a non-holonomic system of non-Chetaev's type with unilateralconstraints in the Nielsen style are *** differential equations of motion for the system above are *** definition and the criteria of Mei symmetry,conditions,and expressions of Mei conserved quantity deduced directlyfrom the Mei symmetry are *** example is given to illustrate the application of the results.

关键词： Nielscn stylc unilatcral constraint non-holonomic system of non-Chctaev's type Mci conscrvcd quantity

Structural Equation and Mei Conserved Quantity of Mei Symmetry for Appell Equations in Holonomic Systems with Unilateral Constraints

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Communications in Theoretical Physics 2009年第10期52卷 572-576页

作者： JIA Li-Qun ZHANG Yao-Yu cui jin-chao LUO Shao-Kai School of Science Jiangnan University Wuxi 214122 China Electric and Information Engineering College Pingdingshan University Pingdingshan 467002 China Institute of Mathematical Mechanics and Mathematical Physics Zhejiang Sci-Tech University Hangzhou 31001 China

Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomie mechanic systems with unilateral constraints axe established. The definition and the criterion of Mei symmetry for Appell equations in holonomic systems with unilateral constraints under the infinitesimal transformations of groups axe also given. The expressions of the structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints expressed by Appell functions are obtained. An example is given to illustrate the application of the results.

关键词： holonomic system with unilateral constraints Appell equation structural equation of Mei symmetry Mei conserved quantity

关于Birkhoff逆问题中Santilli方法的研究

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物理学报 2018年第5期67卷 12-20页

作者：崔金超陈漫廖翠萃江南大学理学院无锡214122 北京理工大学机械与车辆学院北京100081

研究构造Birkhoff动力学函数的Santilli方法.首先,基于Cauchy-Kovalevskaya型方程解的存在性定理,采用反证法证明自治系统总有自治Birkhoff表示;其次,给出更简洁的方法证明Santilli第二方法可以被简化;找到Santilli第三方法中所隐含的... 详细信息

研究构造Birkhoff动力学函数的Santilli方法.首先,基于Cauchy-Kovalevskaya型方程解的存在性定理,采用反证法证明自治系统总有自治Birkhoff表示;其次,给出更简洁的方法证明Santilli第二方法可以被简化;找到Santilli第三方法中所隐含的一种等量关系,提出改进的Santilli第三方法,并研究该方法的MATLAB程序化计算;最后,总结全文并对结果进行讨论.

关键词： Birkhoff逆问题 Birkhoff动力学函数 Santilli方法约束力学系统

Effect of Ti_(p) Content on the Work Hardening and Softening Behavior of Mg-Zn-Ca Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 551-560页

作者： jin-Kai Zhang cui-Ju Wang Yi-Dan Fan chao Xu Kai-Bo Nie Kun-Kun Deng Shanxi Key Laboratory of Advanced Magnesium-Based Materials College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The Ti_(p)/ZX60 composites with different Ti_(p) contents were prepared by semi-solid stirring *** extrusion,the microstructure,work hardening and softening behavior of the Ti_(p)/ZX60 composites were analyzed compared with the ZX60(Mg-6Zn-0.2Ca)*** results showed that the addition of Ti_(p) could not only promote the nucleation of dynamic recrystallized(DRXed)grains,but also be propitious to the refinement of DRXed *** increasing Ti_(p) content,the size of DRXed grains decreased accompanied with increasing volume fraction of DRXed *** the Ti_(p) content increased to 15 vol.%,the average size and volume fraction of DRXed grains reached to~0.32μm and 93.2%,***,both the strength and elongation were improved by the addition of Ti_(p).With increasing content of Ti_(p),a substantial increase in the strength was achieved with little change in the ***,the elongation decreased sharply when the Ti_(p) content further increased to 15 vol.%.The addition of Ti_(p) led to an increase in the work hardening rate,which gradually increased with increasing Ti_(p) ***,the softening rate did not demonstrate the same tendency with increasing Ti_(p) *** the conventional ceramic particles,the Ti_(p) can be deformed in coordination with the matrix alloy,which imparted a higher softening rate to the matrix *** though the softening rate improved as the Ti_(p) content increased from 5 to 10 vol.%,it dropped deeply as the Ti_(p) content increased to 15 vol.%owing to the fracture of Ti_(p) during extrusion.

关键词： Titanium particle content Particle reinforced magnesium matrix composites Work hardening Softening behavior Mechanical properties

Reduction of dinitrogen to ammonia on doped three-atom clusters Nb_(2)M(M=Sc to Cu & Y to Ag)

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Rare Metals 2024年第8期43卷 3810-3818页

作者： Ran Cheng chao-Nan cui Zhi-Xun Luo Beijing National Laboratory for Molecular Science(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was *** key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was *** examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy Nitrogen fixation Ammonia synthesis Theoretical calculations

Appell方程的广义梯度表示及其稳定性分析

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北京理工大学学报 2017年第2期37卷 216-220页

作者：崔金超廖翠萃王勇江南大学理学院江苏无锡214122 广东医学院信息工程学院广东东莞523808

Appell方程是分析力学中的一类重要方程,该方程既可以用来描述完整系统又可以用来描述非完整系统.通过将Appell方程表示为广义梯度形式,进而可以借助梯度系统的某些性质来研究Appell方程的解及其稳定性问题.为此,本文先将梯度系统推广... 详细信息

Appell方程是分析力学中的一类重要方程,该方程既可以用来描述完整系统又可以用来描述非完整系统.通过将Appell方程表示为广义梯度形式,进而可以借助梯度系统的某些性质来研究Appell方程的解及其稳定性问题.为此,本文先将梯度系统推广为包含时间变量的广义梯度系统,再给出Appell方程可化为广义梯度系统的条件,最后利用广义梯度系统的性质来研究Appell方程解的稳定性问题,并结合实际例子说明理论的应用.

关键词：分析力学 Appell方程广义梯度系统解的稳定性分析

Numerical Analysis of Surcharge Effect on Stability and Interaction Mechanism of Slope-Pile-Footing System

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Journal of Earth Science 2024年第3期35卷 955-969页

作者： chao Xu Lei Xue Yuan cui Mengyang Zhai Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Yellow River Laboratory Zhengzhou UniversityZhengzhou 450001China

To investigate the stability and interaction mechanism of the slope-pile-footing system under surcharge effects,the finite difference method(FDM)was adopted to analyze the response laws of the stability of the reinforced slope,evolution of the critical slip surface,stress characteristic of retaining structures,deformation and failure modes of the slope foundation and building footing under surcharge parameters,including the surcharge intensity,the surcharge position,and the surcharge *** results show that surcharge parameters significantly affect the stability and the deformation characteristics of the slope-pile-footing *** speaking,with the increasing surcharge intensity and the decreasing surcharge position and width,the deformation and failure mode of the system will gradually evolve in a direction that is harmful to its *** interaction mechanism of the slope-pile-footing system is further clarified as the load transfer of the building footing,the generation of the additional stress in the slope foundation,and the adjustment of pile bending moment due to the stress ***,the safety of anti-slide piles will determine the stability of the slope foundation and building *** findings are expected to provide guidance for the comprehensive development and utilization of filled slopes after reinforcement.

关键词： slope-pile-footing system slope stability interaction mechanism finite difference method geotechnical engineering safety engineering.

一种求解Birkhoff动力学函数和Lagrange函数的简化方法

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物理学报 2016年第18期65卷 192-198页

作者：崔金超廖翠萃赵喆刘世兴江南大学理学院无锡214122 沈阳药科大学医疗器械学院沈阳110016 辽宁大学物理学院沈阳110036

研究Birkhoff动力学函数和Lagrange函数的简化求解方法.Santilli第二方法作为Birkhoff动力学函数的经典构造方法,其计算公式中隐含的冗余项长期以来被人们所忽视.通过具体证明消去这一冗余项,得到"简化的Santilli第二方法",并由此认识到... 详细信息

研究Birkhoff动力学函数和Lagrange函数的简化求解方法.Santilli第二方法作为Birkhoff动力学函数的经典构造方法,其计算公式中隐含的冗余项长期以来被人们所忽视.通过具体证明消去这一冗余项,得到"简化的Santilli第二方法",并由此认识到:通过求解Birkhoff动力学函数来确定Birkhoff方程等同于确定它的辛矩阵.这种观点为Birkhoff动力学函数的求解提供了新视角.最后,将简化方法得到的推论应用于Lagrange逆问题,得到求解Lagrange函数的简化方法.

关键词： Birkhoff系统 Birkhoff动力学函数 Santilli第二方法 Lagrange函数

Quantum advantages for image filtering on images with efficient encoding and lower-bounded signal-to-noise ratio

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 2-12页

作者： Zidong cui Shan jin Akira Sone Xiaoting Wang Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610051China Key Laboratory of Quantum Physics and Photonic Quantum Information Ministry of EducationUniversity of Electronic Science and Technology of ChinaChengdu 611731China Department of Physics University of MassachusettsBoston 02125USA

Quantum image processing has long been a fascinating field,but establishing the existence of quantum speedup for all images remains *** this study,we aim to identify a subset of images for which a quantum algorithm can be developed with a guaranteed ***,we present a quantum image filtering algorithm that exhibits an exponential speedup for efficiently encoded images with a lower-bounded signal-to-noise *** approach relies on a fixed-point Grover's search to emulate the effect of Hadamard multiplication with the filtering *** demonstrate its effectiveness,we apply our method to three typical filtering ***,we emphasize the significance of the efficient-encoding assumption by illustrating that the quantum speedup may diminish for images lacking efficient *** work underscores the importance of exploring image types and features to realize potential quantum advantages in image processing.

关键词： quantum computing quantum image filtering quantum speedup

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Birkhoff动力学函数成为约束系统第一积分的判别方法

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物理学报 2017年第4期66卷 1-7页

作者：崔金超廖翠萃刘世兴梅凤翔江南大学理学院无锡214122 辽宁大学物理学院沈阳110036 北京理工大学宇航学院北京100018

基于Birkhoff动力学函数包含系统全部运动信息的观点,借鉴Hamilton系统导出第一积分的思路,结合自治、半自治Birkhoff方程的定义和Birkhoff张量反对称性的特点,研究判别给定Birkhoff动力学函数是否是系统第一积分的方法.主要结论包括:... 详细信息

基于Birkhoff动力学函数包含系统全部运动信息的观点,借鉴Hamilton系统导出第一积分的思路,结合自治、半自治Birkhoff方程的定义和Birkhoff张量反对称性的特点,研究判别给定Birkhoff动力学函数是否是系统第一积分的方法.主要结论包括:证明自治系统的Birkhoff函数必是系统的第一积分,而半自治系统的Birkhoff函数一定不是系统的第一积分;针对非自治Birkhoff系统,导出循环积分、类循环积分以及Hojman积分,并讨论积分之间的关系.最后,通过两个例子来说明结论的具体应用.

关键词：约束力学系统 Birkhoff方程 Birkhoff动力学函数第一积分